Free space laser communication originated in the mid-1960's shortly after the generation of light by the first lasers. The first successful laser communication up-link to space was achieved during a series of experiments conducted by NASA in the late 1960's using a ground based argon laser transmitting to a photomultiplier optical receiver feeding data to an rf down link. Information was sent by Morse code at about one-half bit per second. A limiting factor on free space laser communication is the presence of background light, mostly reflected sunlight. Efforts have been made to develop very narrow-band filters matched to the operating wavelengths of available light weight dependable lasers. Some of these efforts are disclosed in "Selected Papers on Free-Space Laser Communication", SPIE Milestone Series, Vol. MS30. Global Positioning Systems (GPS's) currently available provides latitude, longitude and altitude position based on analysis of radio frequency signals from orbiting satellites.
What is needed is a laser portable communication transceiver device which could be used to transmit information point to point over distances ranging from a few feet to several kilometers.